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研究了Ｔｉ３ＡＬ，Ｔｉ３Ａｌ－Ｎｂ及ＴｉＡｌ金属间化合物在９００℃及９５０℃空气中当表面有（０．９Ｎａ，０．１Ｋ）２ＳＯ４盐膜存在时的高温热腐蚀行为．结果表明，Ｔｉ３Ａｌ，ＴｉＡｌ金属间化合物在９００、９５０℃遭受严重的热腐蚀．合金表面均没有形成单一的Ａ１２Ｏ３保护层，而是形成外层为富ＴｉＯ２层，内层为ＴｉＯ２、Ａ１２Ｏ３或Ｎｂ２Ｏ５的混合氧化物层，在氧化膜／合金基体界面形成一些硫化物．合金的腐蚀以电化学机制进行．硫化物的形成也促进了电化学反应的阳极过程．向Ｔｉ３Ａｌ中添加Ｎｂ可以显著地改善其热腐蚀性能，这归因于Ｎｂ促进富Ａｌ氧化物内层的形成．ＴｉＡｌ的耐蚀性能优于Ｔｉ３Ａｌ基合金．
The high temperature hot corrosion behavior of Ti3AL, Ti3Al-Nb and TiAl intermetallic compounds at 900 ℃ and 950 ℃ in the presence of (0.9Na, 0.1K) 2SO4 was studied. The results show that Ti3Al, TiAl intermetallics suffer severe hot corrosion at 900 and 950 ℃. Instead of forming a single A12O3 protective layer on the surface of the alloy, a mixed oxide layer with an outer layer of TiO2-rich and an inner layer of TiO2, A12O3 or Nb2O5 is formed, and some sulfide is formed at the oxide film / alloy matrix interface. Alloy corrosion by electrochemical mechanism. Sulfide formation also promotes the anodic process of electrochemical reactions. The addition of Nb to Ti3Al can significantly improve its hot corrosion performance due to the fact that Nb promotes the formation of an Al rich oxide inner layer. TiAl corrosion resistance than Ti3Al-based alloys.